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As some know i have a r33 gtst series 2 with 209 rwk and the wheelspin really annoys me. i want to change the diff ratio to a lower one. stand me if im correct but i think my one has a 4.36 ratio? and i think the r34gtt has a 4.11? what i want to know is, is the r34 gtt diff centre interchangable with my current one? I want one that fits straight in with no modifications, can anyone sort this out for me, even if they know something else that is interchangable also and that will handle more power if i decide to. I also want it for the better top end and lower rev range whilst on the freeway at 100kph.

many thanks :)

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I ran a 270rwkw street tune for a while.

225 tyres, hardly an issue with wheelspin.

I'd be looking at the suspension, quality of the tyres, diff condition and driving style :)

im getting a set of coilovers within the next 6 months, for now i just want to change the diff as i drive alot on the freeway and the constant high revving annoys me lol

As some know i have a r33 gtst series 2 with 209 rwk and the wheelspin really annoys me. i want to change the diff ratio to a lower one. stand me if im correct but i think my one has a 4.36 ratio? and i think the r34gtt has a 4.11? what i want to know is, is the r34 gtt diff centre interchangable with my current one? I want one that fits straight in with no modifications, can anyone sort this out for me, even if they know something else that is interchangable also and that will handle more power if i decide to. I also want it for the better top end and lower rev range whilst on the freeway at 100kph.

many thanks :thumbsup:

The R33's run a 4.11:1 diff ratio; the R32's run the 4.363.

Also. A higher diff ratio is numerically lower i.e 3.7:1, a lower diff ratio is numberically higher i.e 4.3:1.

Yes a higher ratio diff will help prevent wheel spin but it does make the car feel like it takes longer to come up on boost when toodling around then mashing the throttle from a low rpm.

First gear was much more enjoyable and usable however the trade off in the snap hard on boost in second and third gear simply was not worth it.

100km/h cruising speed did drop the rev's a little but unless you drop to a 3.7:1 or there abouts its really not that noticable.

3.7:1 will have your 0-100 times increase noticably. So don't do it. I have and went straight back to a 4.3.

If the engine noise gets to you at 100km/h shove in another muffler just after the cat.

Traction, you shouldn't have issues with only 209rwkw; as others have suggested definitely take a good look at your diff, suspension and tyres. Apart from tyres which is obvious the diff's worn VLSD is usually the culprit.

One thing that prevents them being 100% interchangable is the half shafts bolt pattern.

R33 is 5bolt (1x5), R34 is 6 bolt? and S15 I can't remember. :thumbsup:

Unsure on spline; I'm almost certian if the R34 is 6bolt it will also have the larger spline.

Again... If its to reduce wheel spin then your barking up the wrong tree especially with only 209rwkw which is bugger all.

If its 'only' to drop rev's at 100km/h then yes.. BUT acceleration rate will suffer as a result.

The J30 diff isn't a simple drop in. I would expect the pumpkin to be the same as the R33 but the half shafts are different.

You will have to drop your diff center in to the J30 pumpkin and then slide in your half shafts; or grab the crown and pinion from the J30 and have it fitted to your diff housing.

Either way your up for around $300 ish for the J30 diff and another $300ish to get it working. So all up $600 ish + oil.

You really are better off putting that $600 towards a good mechanical. If you want a good 100km/h cruiser buy a family wagon. :thumbsup:

Again... If its to reduce wheel spin then your barking up the wrong tree especially with only 209rwkw which is bugger all.

If its 'only' to drop rev's at 100km/h then yes.. BUT acceleration rate will suffer as a result.

The J30 diff isn't a simple drop in. I would expect the pumpkin to be the same as the R33 but the half shafts are different.

You will have to drop your diff center in to the J30 pumpkin and then slide in your half shafts; or grab the crown and pinion from the J30 and have it fitted to your diff housing.

Either way your up for around $300 ish for the J30 diff and another $300ish to get it working. So all up $600 ish + oil.

You really are better off putting that $600 towards a good mechanical. If you want a good 100km/h cruiser buy a family wagon. :thumbsup:

i already have a family wagon lmao!!! lol. its more for rev drop than wheelspin. what is the j30 diff?

J30 is a type of nissan just like the R32 R33 etc

As I said.. before, a 3.9:1 won't drop 100km/h rpm all that noticably.

The rolling dia of your 265/35 18's is slightly larger than stock so at 100km/h you will already be reving slightly lower AND your speedo will be slightly out.

At 100km/h with your 4.11:1 diff ratio, 5th gear ratio and 265/35/18's the engine will be ticking over at :

4.1 ratio - 2551rpm

3.9:1 ratio - 2421rpm

3.7:1 ratio - 2297rpm

4.3:1 ratio that is shorter you'll be at 2708rpm

If you ran factory spec rolling dia (631.90) tyres (205/55/16) at 100km/h with stock ratio's etc you'd be ticking over at 2591rpm. So with your larger tyres you've dropped 40rpm off your 100km/h cruising speed.

Also the stock tacho reads slightly higher than it really is. :thumbsup:

So you have to ask yourself... Is 100rpmish really worth the slower/duller acceleration? I've done it and I definitely do not think so; enough so that I had the diff out a couple of weeks later and the std diff ratio shoved back in it.

thanks mate. i heard the s13 turbo auto model has a 3.9 ratio and fits straight in? correct me if im wrong

I added to my previous post with some figures. :thumbsup:

The S13 diff isn't a drop in due to its different housing. So again you will be forced to swap the ratio from that diff in to your housing. Of which will blow out ot $600 odd by the time you buy the diff and have it fitted.

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